NZ332019A - High water content porous polymer comprising a perfluoropolyether unit - Google Patents

Abstract

A porous polymer prepared under porosity-promoting condition as defined in the specification comprising one or more perfluoropolyether units having a water content when fully swollen in water which is higher than that of the same polymer if polymerized under conventional conditions is claimed. The perfluoropolyether units are preferably of the formula (PFPE):-OCH2-CF2O(CF2CF2O)x-(CF2O)y-CF2CH2O- wherein the CF2CF2O and CF2O units may be randomly distributed or distributed as blocks throughout the chain and wherein x and y may be the same or different such that the molecular weight of the perfluorinated polyether is in the range of from 242 to 4,000. The porous polymers are suitable for soft contact lenses.

Description

New Zealand Paient Spedficaiion for Paient Number 332019 High Water Content Porous Polymer The present invention relates to porous polymers comprising a perfluoropolyether unit, to a process for producing such porous polymers, in particular to a process for polymerising or copolymensing monomers incorporating perfluoropolyethers to form porous polymers, to articles made of or comprising porous polymers comprising a perfluoropolyether unit, such as membranes or ophthalmic devices, s g contact lenses, and to the use of porous polymers comprising perfluoropolyether units as articles, such as membranes or ophthalmic devices, e g contact lenses In'fTfany.applications it has been found advantageous for polymers to be porous The degree of porosity required dsjiends on the application For example, membrane filtration depends on the use of microporous polymers to effect separations of various materials Also macroporous sheets of chemically resistant polymers find extensive use as cell dividers in cells for electrolysis or electricity storage Pores may be formed in the polymer during the process of manufacturing an article of the desired shape or may be formed in the article after manufacture There are a variety of methods known in the art for the introduction of porosity into synthetic polymers, such as those described in WO 90/07575, WO 91/07687, US-A-5,244,799, US-A-5,238,613, or US-A-4,799,931 Some rely on a drilling or etching process after the polymer has been formed Thus, high energy particles or electromagnetic radiation, such as that emitted from lasers, have been used as described in WO 91/07687 These processes are general'y labour intensive and time consuming Less commonly, the porosity may be an inherent property of the polymer and the porosity maintained as the polymer is formed into the desired shape for a particular application It is particularly advantageous for the porosity to be introduced during the polymer forming steps This is generally economical and, in appropriate cases, good control over the porosity and pore size can be achieved Polymers based on perfluoropolyethers, in general, have many unique and desirable properties These include resistance to fouling by proteinaceous and other materials, Printed from Mimosa 18 03 29 WO 97/35906 PCT/EP97/01410 outstanding flexibility, transparency, high resistance to temperature extremes, and exceptional chemical and oxidation resistance These properties would make perfluoro-polyether based polymers particularly suitable for a variety of applications and would be particularly suited for use as membranes if methods were available for the economic introduction of porosity Indeed, there has been a long-felt need for membrane materials with the above atti ibutes Polytetrafluoroethylene-based (PTFE) membrane materials provide a partial solution to this need However, unlike perfluoropolyether-based polymers, which can be readily cured and formed into articles by in-situ polymerisation, PTFE-based materials suffer from the disadvantage of being difficult to fabricate and manufacture into articles In addition, stretching processes such as those described in US-A-3,953,566 (Gore) give a somewhat limited range of size and shape of the porosities and are difficult to control Because of the properties mentioned above perfluoropolyether based polymers are highly desirable materials for contact lenses and other ophthalmic devices (US-A-4,440,918, US-A-4,818, 801), if such materials could be made porous to allow transfer of tear fluids or nutrients their usefulness would be considerably enhanced Despite the obvious potential advantages of these materials, porous perfluoropolyether polymers have not previously been available In certain polymers porosity may be an interpenetrating network of holes, closed cells or a combination thereof This may be achieved by polymerization in the presence of an insoluble material often referred to as a porogen Subsequent leaching of the porogen gives rise to interstices throughout the formed polymer matenal Sodium chloride is one such matenal that has been used A disadvantage of this process is the drfficulty of stabilising the suspension of porogen in the polymerisation mixture Unstable suspensions can lead to an inhomogeneous and unacceptable product In many cases, extensive optimisation of the viscosity of the system and the type of porogen is needed to obtain a satisfactory result In addition the procedure is limited in terms of the availability of porogens suitat i for introducing the desired ranges of pore sizes A convenient and versatile method of obtaining porous materials is the polymerisation of co-continuous microemulsions Microemulsion polymerisation involves the polymerisation of a Printed from Mimosa 18 03 29 stable isotropic mixture of an oil phase and a water phase stabilized by surfactants The oil phase generally contains the polymerisable monomer, which polymenses around either contiguous droplets of the water phase stabilized by surfactants or about a co-continuous water phase Typically, organic solvents are not used in the water phase It will be appreciated that porous materials derived from perfluoropolyethers possess unusual characteristics in their interaction with other substances An unusually low surface energy is one such characteristic The low surface energy and low propensity to adsorb many common materials is, in part, responsible for their outstanding resistance to fouling and degradation and the utility of fluoropolymers in applications requiring soiling resistance or non-stick properties A consequence of the low surface energy and solubility of fluorochemicals, is that stable emulsions and microemulsions in aqueous and other commoii media are very difficult to achieve For example, standard surfactants well-known in the art are ineffective in stabilising aqueous microemulsions containing perfluoropolyethers Accordingly, standard procedures for making microemulsions are ineffective for perfluoropolyether-based monomers It is an object of the present invention to provide porous polymers comprising one or more perfluoropolyether units having a water content when fully swollen in water which is higher than that of the same polvmer if polymerized under conventional conditions It is a further object of the present invention to provide porous polymers compnsing one or more perfluoropolyether units characterized in that the water content of said polymer, when fully swollen in water, is above 23 weight percent It is a further object of the present invention to provide porous polymers comorising one or more perfluoropolyether units which are either homopolymers or copolymers with a hydrophobic comonomer characterized in that the water content of said polymer, when fully swollen in water, is above 5 weight percent It is a still further object of the invention to provide articles made of one or more of the above mentioned porous polymers, or comprising one or more of the above mentioned porous polymers, which articles may be for example membranes or ophthalmic devices, such as, preferably, contact lenses Printed from Mimosa 18 03 29 It is another object of the invention to provide processes for the manufacture of the above mentioned porous polymers More specifically, the invention is directed to a porous polymer comprising at least one macromonomer having one or more perfluoropolyether units characterized in that the water contents of said polymer, when fully equilibrated with water, is above 23 weight percent A preferred range of water content is 25 to 60 weight %, an even more preferred range is 30 to 55 weigt % In addition, the invention is directed to a porous polymer which is a homopolymer of at least one macromonomer having one or more perfluoropolyether units or a copolymer of such macromonomer with a hydrophobic comonomer characterized in that the water contents, when fully equilibrated with water, is above 5 weight percent A preferred range of water content is 5 to 60 weight %, an even more preferred range is 10 to 55 weight %, and a very preferred range is 25 % to 52 weight % In a preferred embodiment the polymerizable component includes at least one macromonomer having at least one perfluoropolyether unit It will be understood by those skilled in the art that the terms "perfluoropolyether unit" and " PFPE unit" mean preferably a moiety of formula PFPE -OCH2CF20 ( CF2CF20 )x( CF20 )y CF2CH20- (PFPE) wherein the CF2CF20 and CF20 units may be randomly distributed or distributed as blocks throughout the chain and wherein x and y may be the same or different such that the molecular weight of the perfluorinated polyether is in the range of from 242 to 4,000 Preferably x in Formula (PFPE) is in the range of from 0 to 20, more preferably in the range from 8 to 12, and y is in the range from 0 to 25, more preferably in the range from 10 to 14 Even more preferred, x and y in Formula (PFPE) are both different from zero such that x is in the range of from 1 to 20, more preferably in the range from 8 to 12, and y is in the range from 1 to 25, more preferably in the range from 10 to 14 Printed from Mimosa 18 03 29 WO 97/35906 PCT/EP97D1410 Preferred macromonomers having at least one perfluoropolyether unit include, but are not limited to, ihose of formula I, II and III as specified hereinafter Macromonomers of formula (I) Q-(PFPE- L)n.rPFPE-Q (I) macromonomers of formula (II) Q-B-(L-B)n-T (II) and macromonomers of formula (III) Q-PFPE-L-M-L-PFPE-Q (III) wherein in these formulae Q may be the same or different and is a polymerizable group, PFPE is a divalent residua of formula (PFPE) as hereinbefore defined, L is a difunctional linking group, n is at least 1, in macromonomers of formula (II) each B may be the same or different and is a difunctional block of molecular weight in the range of from 100 to 4000 and wherein at least one B is a perfluorinated polyether of formula (PFPE), in macromonomers of formula (II) T is a univalent terminal group which is not polymerisable by free radicals but which may contain other functionality, and in macromonomers of formula (III) M is a residue from a difunctional polymer or copolymer comprising silicone repeat units of formula IV having a molecular weight preferably in the range of from 180 to 6000 and end functionality as described below R1 OS, ("V) Printed from Mimosa 18 03 29 wherein R1 and may be the same or different and are selected from the group consisting of hydrogen, alkyl, aryl, halosubstituted alkyl and the like R1 and R2 are preferably methyl As mentioned, one embodiment of the invention Is directed to a porous polymer comprising at least one macromonomer having one or more perfluoropolyether units characterized in that the water contents of said polymer, when fully equilibrated with water, is above 23 weight percent Such a porous polymer is preferably a copolymer of o^e or more macromonomers having one or more perfluoropolyether units, preferably of formula I, II or III, with one or more hydrophilic comonomers, or with a mixture of a hydrophobic and a hydrophilic comonomer in which mixture the hydrophilic comonomer has a higher weight percentage than the hydrophobic comonomer Polymers based on macromonomers and only hydrophilic comonomers are preferred in this context Examples of preferred comonomers are provided hereinafter As also mentioned, another embodiment of the invention is directed to a poious polymer which is a homopolymer of at least one macromonomer having one or more perfluoropolyether units or a copolymer of such macromonomer with a hydrophobic comonomer characterized in that the water contents, when fully equilibrated with water, is above 5 weight percent In this case the polymer is either a homopolymer of a single macromonomer having one or more perfluoropolyether units, or it is an interpolymer of more than one macromonomers having one or more perfluoropolyether units, or it is a copolymer of one or more macromonomers having one or more perfluoropolyether units, preferably of formula I, II or III, with one or more hydrophobic comonomers, or with a mixture of a hydropnobic and a hydrophilic comonomer in which mixture the hydrophobic comonomer has a higher weight percentage than the hydrophilic comonomer Polymers based on macromonomers and only hydrophobic comonomers are preferred in this context Examples of preferred comonomers are provided hereinafter One of the essential distinctive features of the present invention is that the porous polymers comprising one or more perfluoropolyether units have a water content when fully swollen in water which is higher than that of the same polymer if polymerized under conventional conditions This definition is to be understood in the context of this invention in that the Printed from Mimosa 18 03 29 PCT7EP97/01410 claimed porous polymers do have their porosity, and the higher water content resulting therefrom, in the absence of any mechanical process steps following the polymerization step, such as mechanical drilling or etching steps "Conventional conditions" is understood to mean those conditions which have been disclosed already for polymerization of polymers comprising perfluoropolyether units In order to further illustrate the "conventional conditions' it is to be understood that said conditions most preferably exclude any porosity promoting conditions, while porosity promoting conditions are chosen for making the porous polymers of the present invention Such porosity promoting conditions are, essentially, use of porogens during polymerization, polymerization siarting from co-continuous microemulsions, or selection of a solvent which forms a homogenous solution with the components to be polymenzed, but displays the effect of forming a discrete phase during or at the end of the polymerization which discrete organic solvent phase forms an interpenetrating network throughout the mixture or is dispersed through the mixture In contrast thereto, the "conventional conditions" referred to hereinbefore and hereinafter, define essentially a polymerization process which is conducted starting from a homogenous phase, e g from a homogenous solution in an organic solvent of the components to be polymerized, which phase remains a homogenous phase (then the polymer formed is a soluble polymer), or which homogenous phase is transformed into a solvent phase and, separately therefrom, a continuous polymer phase at the end of the polymerization (then the polymer formed is a polymer which is unsoluble in the chosen solvent) Typical examples of "conventional conditions" are provided in comparative examples 13 and 14 In the above formulae I, II and III, respectively, the following definitions apply It is preferred that n is in the range of from 1 to 5, more preferably n is in the range of from 1 to 3 Macromonomers where n is 1 are particularly preferred Q is a polymerizable group which preferably comprises an ethylenically unsaturated moiety which can enter into a free radical polymerization reaction Preferably Q is a group of the formula A Pi-(Y)m--dithioacylhalides, a.to-dicarboxylic acids, a,to-dithiocarboxylic acids, a,io-dianhydrides, a.w-dithioisocyanates, a.to-dilactones, a,u>-dialkylesters, a.to-dihalides, a.w-dialkylethers, a,co-dihydroxymethylamides It is preferred that the linking group be a bivalent residue (-C(O)-NH-R-NH-C(O)-) of a dnsocyanate or the corresponding residue of a dithioisocyanate, wherein R is a divalei it organic radical having up to 20 carbon atoms The divalent radical R is, for example, alkylene, arylene, alkylenearylene, arylenealkylene or arylenealkylenearylene having up to 20 carbon atoms, a saturated bivalent cycloaliphatic group having 6 to 20 carbon atoms or cycloalkylenealkylenecycloalkylene having 7 to 20 carbon atoms In a preferred embodiment, R is alkylene, arylene, alkylenearylene, arylenealkylene or arylenealkylenearylene having up to 14 carbon atoms or a saturated divalent cycloaliphatic group having 6 to 14 carbon atoms In a particularly preferred embodiment, R is alkylene or arylene having up to 12 carbon atoms or a saturated bivalent cycloaliphatic group having 6 to 14 carbon atoms In a preferred embodiment, R is alkylene or arylene having up to 10 carbon atoms or a saturated bivalent cycloaliphatic group having 6 to 10 carbon atoms In a particularly preferred meaning, R is a radical derived from a dnsocyanate, for example from hexane 1,6-diisocyanate, 2,2,4-trimethylhexane 1 6-dnsocyanate, tetramethylene dnso cyanate, phenylene 1,4-dnsocyanate, toluene 2,4-dusocyanate, toluene 2,6-dnsocyanate, m- or p-tetramethylxylene dnsocyanate, isophorone dnsocyanate or cyclohexane 1,4-diiso-cyanate Printed from Mimosa 18 03 29 Aryl is a carbocyclic aromatic radical which is unsubstituted or substituted preferably by lower alkyl or lower alkoxy Examples are phenyl, tolyl, xylyl, methoxyphenyl, t-butoxy-phenyl, naphthyl and phenanthryl Arylene is preferably phenylene or naphthylene, which is unsubstituted or substituted by lower alkyl or lower alkoxy, in particular 1,3-phenylene, 1,4-phenylene or methyl-1,4-phenylene, 1,5-naphthylene or 1,8-naphthylene A saturated bivalent cycloaliphatic group is preferably cycloalkylene, for example cyclo-hexylene or cyclohexylene(lower alkylene), for example cyclohexylenemethylene, which is unsubstituted or substituted by one or more lower alkyl groups, for example methyl groups, for example trimethylcyclohexylenemethylene, for example the bivalent isophorone radical For the purposes of the present invention, the term "lower" in connection with radicals and compounds, unless defined otherwise, denotes, in particular, radicals or compounds having up to 8 carbon atoms, preferably having up to 4 carbon atoms Lower alkyl has, in particular, up to 8 carbon atoms, preferably up to 4 carbon atc~~s, and is, for example, methyl, ethyl, propyl, butyl, tert-butyl, pentyl, hexyl or isohexyl Alkylene has up to 12 carbon atoms and can be straight-chain or branched Suitable examples are decylene octylene, hexylene, pentylene, butylene, propylene, ethylene, methylene, 2-propylene, 2-butylene, 3-pentylene, and the like Lower alkylene is alkylene having up to 8 carbon atoms, particularly preferably up to 4 carbon atoms Particularly preferred meanings of lower alkylene are propylene, ethylene and methylene The arylene unit in alkylenearylene or arylenealkylene is preferably phenylene, unsubstituted or substituted by lower alkyl or lower alkoxy, and the alkylene unit therein is preferably lower alkylene, such as methylene or ethylene, in particular methylene These radicals are therefore preferably phenylenemethylene or methylenephenylene Lower alkoxy has, in particular, up to 8 carbon atoms, preierably up to 4 carbon atoms, and is, for example, methoxy, ethoxy, propoxy, butoxy, tert-butoxy or hexyloxy Printed from Mimosa 18 03 29 Arylenealkylenearylene is preferably pheny!ene(lower alkylene)phenylene having up to 8, in particular up to 4, carbon atoms in the alkylene unit, for example phenyleneethylene-phenylene or phenylenemethylenephenylene Some examples of preferred dusocyanates from which bivalent residues L are derived include trimethylhexamethylenednsocyanate (TMHMDI), isophorone dnsocyanate (IPDI), methyienediphenyl dnsocyanate (MDI) and 1,6-hexamethylenednsocyanate (HMDI) The blocks B may be monomeric, oligomenc or polymeric The molecular weights and chemical composition of each block B may be the same or different, provided that they fall within the molecular weight range specified above The blocks B may be hydrophobic or hydrophilic, provided that at least one of the blocks is of formula (PFPE) Other suitable blocks B may be derived from poly(alkylene oxides) When one or more of the blocks B is hydrophilic, these blocks are particularly preferably derived from poly(alkylene oxides), more preferably from poly(lower alkylene oxides), most preferred from the polyethylene glycols It is most preferred that the B blocks are selected from blocks of formula (PFPE) and poly(alkylene oxides), provided that at least one of the blocks is of formula (PFPE) In two very preferred embodiments of the invention there are two B blocks in a macromonomer of formula II which are either both of formula (PFPE), or one of which is of formula (PFPE) while the other is denved from a poly(alkylene oxide), preferably from a poly(lower alkylene oxide), most preferred from polyethylene glycols "Derived from a ooly(alkylene oxide)" in the context of the definition of the B blocks means that such a B block differs from a poly(alkylene oxide) in that the two terminal hydrogens have been abstracted from such poly(alkylene oxide) In order to exemplify this, B denotes, if derived from a polyethylene glycol, -(OCH2CHi)aO- wherein a is the index indicating the number or repeating ethyl eneoxy groups The terminal group T is a univalent terminal grouD which is not polymerizable by free radicals but which may contain other functionality Preferred terminal groups are hydrogen, alkyl, substituted a'kyl, aryl or substituted aryl More preferred groups T are hydrogen, lower alkyl and phenyl Suitable substituents for Q or T may be selected from alkyl, alkenyl, alkynyl, aryl, halo, haloalkyl, haloalkenyl, haloalkynyl, haloaryl, hydroxy, alkoxy, alkenyloxy, aryloxy, haloalkoxy, haloalkenyloxy, haloaryloxy, amino alkylamino, alkenylamino, alkynylamino arylarnino, acyl, aroyl, alkenylacyl, arylacyl, acylamino alkylsulphonvioxy, arylsulphenvloxy Printed from Mimosa 18 03 29 WO 97/35906 PCT/EP97/01410 heterocyclyl, heterocycyloxy, heterocycylamino, haloheterocyclyl, alkoxycarbonyl, alkylthio, alkylsulphonyl, arylthio, arylsulphonyl, aminosulphonyl, dialkylamino and dialkylsulphonyl, having up to 10 carbon atoms The difunctional polymer from which M is derived contains an independently selected terminal functionality at each end which may react with the precursor of the linking group L so that a covalent linkage is formed The preferred terminal functionality is hydroxy! or amino Such functionality may be joined to the siloxane units in M by means of an alkylene group or other non reactive spacer Preferred terminal moieties are hydroxyalkyl, hydroxyalkoyvalkyl and alkylarnino Especially preferred hydroxyalkyls are hydroxypropyl and hydroxybutyl, especially preferred hydroxyalkoxyalkyls are hydroxyethoxyethyl and hydroxyethoxypropyl Preferred^1 and R2 groups are methyl Preferred M residues in formula III as specified above are of formula B X,—AJk—Si— ^ I R r O—Si—f-Alk—X, I ^ "4 (B) where n is an integer from 5 to 100, Alk is alkylene having up to 20 carbon atoms, uninterrupted or interrupted by oxygen, the radicals R,, R2, R3 and R4, independently of one another, are alkyl, aryl or halosubstituted alkyl, and X3 is -0- or NH In a preferred meaning, n is an integer from 5 to 70, particularly preferably 8 to 50, in particular 10 to 28 In a preferred meaning, the radicals Ri, R2, R3 and R< are, independently of one another, lower alkyl having up to 8 carbon atoms, particularly preferably lower alkyl having up to 4 carbon atoms, especially lower alkyl having up to 2 carbon atoms A further particularly preferred embodiment of Ri, R2, R3 and R« is methyl Alkylene interrupted by oxygen is preferably lower alkylene-oxy lower alkylene having up to 6 carbons in each of the two lower alkylene moieties, more preferably lower alkylene-oxy- Printed from Mimosa 18 03 29 lower alkylene having up to 4 carbons in each of the two lower alkylene moieties, examples being ethylene-oxy-ethylene or ethylene-oxy-propylene Halosu^stituted alkyl is preferably lower alkyl substituted by one or more, especially up to three, halogens such as fluoro, chloro or bromo, examples being trrfluoromethyl, chloromethyl, heptafluorobuty! or bromoethyl A prerferred macromonomer is of formula I wherein n is in the range of from 2 to 5, L is a bivalent residue (-C(O)-NH-R-NH-C(O)-) of a dnsocyanate wherein R is alkylene, arylene, alkylenearylene, arylenealkylene or arylenealkylenearylene having up to 14 carbon atoms or a saturated divalent cycloaliphatic group having 6 to 14 carbon atoms, and Q is a compound of formula A wherein Pi is alkenyl of up to 4 carbon atoms, Y is -COO-, R' is alkylene of up to 4 carbon atoms, Xi is -NHCOO- and m and p are each one A preferred macromonomer of formula I is one in which n is in the range of from 2 to 5, L is the bivalent residue derived from trimethylhexamethylene dnsocyanate (TMHMDI) and Q is the residue derived from isocyanatoethyl methacrylate A preferred embodiment of this invention is directed to a macromonomer of formula 1 CH2=C(CH3)COOC2H4NHCO-{-PFPE-CONH R-NHCO )n 1-PFPE-CONHC2H4OCOC(CH3)=CH2 (Formula 1) wherein PFPE is a perfluorinated polyether of formula (PFPE) as herein defined, wherein x is in the range of from 8 to 10 and y is in the range of from 10 to 14, n > 1 0, and R is alkylene or arylene having up to 12 carbon atoms or a saturated bivalent cycloaliphatic group having 6 to 14 carbon atoms In a preferred embodiment of the present invention there is provided a macromonomer of formula 2 CH2=C(CH3)COOC2H4NHCO-(-PFPE CONH-R-NHCO-)n -|-PFPE-CONHC2H4OCOC(CH3)=CH2 (Formula 2) Printed from Mimosa 18 03 29 wherein PFPE is a perfluorinated polyether of formula (PFPE) as herein defined, n>1 0, R is the trimethylhexamethylene component of TMHMDI, and wherein x is in the range of from 8 to 10 and y is in the range of from 10 to 14 in a preferred embodiment of the present invention there are provided macromonomers of formula II which correspond to formulae 3 to 6 wherein PFPE is of formula (PFPE) wherein x and y are as defined hereinbefore, R is alkylene, arylene, alkylenearylene, arylenealkylene or arylenealkylenearylene having up to 14 carbon atoms or a saturated divalent cycloaliphatic group having 6 to 14 carbon atoms and PEG is derived from polyethylene glycol Preferably PEG has a molecular weight in the range of from 200 to 2000 In an even more preferred embodiment of the present invention there are provided macromonomers of formulae 7 to 10 wherein PFPE is of formula (PFPE) wherein x and y are as defined hereinbefore, wherein R is the trimethylhexamethylene component of TMHMDI, and PEG is derived from polyethylene glycol Preferably PEG has a molecular weight in the range of from 200 to 2000 It is also preferred in this embodiment that x is 10 and y is 12 A preferred macromonomer of formula III is one in which the molecular weight of the perfluorinated polyether is in the range of from 800 to 4,000, L is the bivalent residue derived from trimethylhexamethylene dnsocyanate (TMHMDI) and Q is the residue derived from isocyanatoethyl methacrylate It is particularly preferred that the molecular weight of the perfluorinated polyether is about 2,000 and the molecular weight of M is about 1,000 CH^CfCHslCOOC^NHCO-PFPE-CONH-R-NHCO-PFPE-H CH^C^HaJCOCXy^NHCO-PEG-CONH-R-NHCO-PFPE-H CH2=C(CH3)COOC2H4NHCO-PFPE-CONH-R-NHCO-PEG-CH3 CH2=C(CH3)COCX^H4NHCO-PFPE-CONH-R-NHCO-PEG-H (3) (4) (5) (6) CH2=C(CH3)COOC2H4NHCO PFPE-CONH-R-NHCO-PFPE-H CH2=C(CH3)COOC2H4NHCO-PEG-CONH-R-NHCO-PFPE-H CH2=C(CH3)COOC2H4NHCO-PFPE-CONH-R-NHCO-PEG-CH: CH2=C(CH3)COOC2H

Claims (1)

1. WO 97/35906 PCT/EP97/01410 -45 - Darocur 03 * For Monocon 400 definition see example 18 The permeability of the lens to a solution of BSA was monitored by the U V spectroscopic technique After 24 hours the absorbance reading for the lens was A280 = 0 164 After hydration the water content of the lens was measured to be 31 % (w/w);Example 29 The following formulations were placed in flat polypropylene lens moulds (0 2mm thick, 20mm diameter) and polymerised for 3 hours over the irradiation generated from a U V lamp at a wavelength of 365nm All parts are by weight Macromomoner (X) in this example is a macromonomer of formula I wherein n is 2 9;A;B;Macromonomer (X);0 500;0 255;Isopropanol;0 248;_;Cyclohexanol;0 118;Trifluoroethanol;0 422;0 298;Darocur;03;03;The permeability of the lenses to a solution of BSA was monitored by the U V spectroscopic technique After 24 hours the absorbance reading for lens A was A280=0 64 and lens B was A280=0 33 After hydration the water content of lenses A and B was measured to be 33 and 28 % (w/w) respectively;Printed from Mimosa 18 03 29;1;- 46 -;The claims defining the invention are as follows;1 A polymer prepared under porosity-promoting conditions comprising one or more perfluoropolyether units having a water content when fully swollen in water which is higher than that of the same polymer if polymerized under conventional conditions;2 A porous polymer according to claim 1 comprising at least one macromonomer having one or more perfluoropolyether units characterized in that the water contents ot said polymer, when fully equilibrated with water, is above 23 weight percent;3 A porous polymer according to claim 1 which is a homopolymer of at least one macromonomer having one or more perfluoropolyether units or a copolymer of such macromonomer with a hydrophobic comonomer characterized in that the water contents, when fully equilibrated with water, is above 5 weight percent;4 A porous polymer according to any of claims 1 to 3 wherein the perfluoropolyether units are of formula PFPE;wherein the CF2CF2O ana CF2O units may be randomly distributed or distributed as blocks throughout the chain and wherein x and y may be the same or different such that the molecular weight of the perfluorinated polyether is in the range of from 242 to 4,000;5 A porous polymer according to any of claims 1 to 4 wherein at least one macromonomer is of formula (I);-OCH2CF20 ( CF2CF20 )x( CF20 )y CF2CH20- (PFPE);Q-(PFPE- L)n_rPFPE-Q;(!);wherein;Q may be the same or different and is a polymerizable group PFPE is a moiety of formula PFPE;w/O 97/35906;PCT/EP97/01410;- 47 -;-0CH2CF20 ( CF2CF20 )x( CF20 )y CF2CH20- (PFPE);wherein the CF2CF20 and CF20 units may be randomly distributed or distnbuted as blocks throughout the chain and wherein x and y may be the same or different such that the molecular weight of the perfluorinated polyether is in the range of trom 242 to 4,000,;L is a difunctional linking group, and n is at least 1;6 A porous polymer according to any of claims 1 to 4 wherein at least one macromonomer is of formula (II);Q-B-(L-B)n T (II);wherein;Q may be the same or different and is a polymerizable group,;L is a difunctional linking group,;n is at least 1,;each B may be the same or different and is a difunctional block of molecular weight in the range of from 100 to 4000 and wherein at least one B is a perfluorinated polyether of formula (PFPE),;PFPE is a moiety of formula PFPE;-OCH2CF2C> ( CF2CF20 )x( CF20 )y CF2CH20- (PFPE);wherein the CF2CF20 and CF20 units may be randomly distributed or distributed as blocks throughout the chain and wherein x and y may be the same or different such that the molecular weight of the perfluorinated polyether is in the range of from 242 to 4,000, and T is a univalent term'nal group which is not polymerisable by free radicals but which may contain other functionality;7 A porous polymer according to any of claims 1 to 4 wherein at least one macromonomer is of formula (III);Printed from Mimosa 18 03 29;WO 97/35906;PCT/EP97/01410;- 48 -;Q-PFPE-L-M-L-PFPE-Q;(III);wherein;Q may be the same or different and is a polymerizable group, PFPE is a moiety of formula PFPE;-OCH2CF20 (CF2CF20 )x( CF20 )y CF2CH20- (PFPE);wherein the CF2CF20 and CF20 units may be randomly distributed or distributed as blocks throughout the chain and wherein x and y may be the same or different such that the molecular weight of the perfluorinated polyether is in the range of from 242 to 4,000 L is a difunctional linking group,;M is a residue from a difunctional polymer or copolymer comprising silicone repeat units of formula IV having a molecular weight preferably in the range of from 180 to 6000 and end functionality as described herein wherein FO and may be the same or different and are selected from the group consisting of hydrogen, alkyl, aryl, halosubstituted alkyl and the like;8 An article comprising a porous polymer as claimed in any of claims 1 to 7;9 An article according to claim 8 which is an ophthalmic device;10 An article according to claim 9 which is a contact lens;11 An article according to claim B which is a membrane;12 A process for the production of a porous polymer of claim 1 comprising the steps or;R;OSi;(IV);Printed from Mimosa 18 03 29;WO 97/35906;PCT/EP97/01410;-49 -;i) forming a mixture comprising a polymerizable component and an organic solvent wherein the polymerizable component comprises at least one macromonomer having at least one perfluoropolyether unit,;li) polymerizing said mixture wherein immediately after the polymerization of said mixture at least a substantial proportion of said organic solvent is in the form of a discrete phase and wherein said discrete organic solvent phase forms an interpenetrating network throughout the mixture or is dispersed throughout the mixture, and in) removing the discrete organic solvent phase;13 A process according to claim 12 wherein the organic solvent is dusopropyl ether;14 A process for producing a porous polymer of claim 1 comprising the steps of;1) dispersing a porogen in a continuous monomer component phase wherein said continuous monomer component phase comprises at least one monomer having at least one perfluoropolyether unit and wherein said porogen is an optionally substituted poly(alkylene)glycol,;2) thereafter polymerising the continuous monomer phase, and;3) removing the porogen from the porous polymer;15 A process according to claim 14 wherein the porogen is polypropylene glycol;16 An article compnsing a porous polymer obtainable according to the process of any of claims 12 or 13;17 An article comprising a porous polymer obtainable according to the process of any of claims 14 or 15;18 An article according to claim 16 which is a contact lens;19 An article according to claim 17 which is a contact lens;Printed from Mimosa 18 03 29;/■ "J ^ * / -50- '/ 0 20 A polymer according to claim 1, substantially as herein described with reference to the examples 1 to 12 21 A polymer according to any one of claims 1 to 7, substantially as herein described with reference to the accompanying examples thereof 22 An article according to claim 8, substantially as herein described with reference to examples 15 to 29 23 An article according to any one of claims 8 to 11, substantially as herein described with reference to examples 15 to 29 24 A process according to claim 12, substantially as herein described with reference to examples 1 to 12 25 A process according to any one of claims 12 to 15, substantially as herein described 26 An article according to any one of claims 16 to 19, substantially as herein described with reference to examples 15 to 29